What is the locus of point that is equidistant from points P(1,3) and Q(3,5)?
The correct answer is: A
Explanation

Locus of a point equidistant from two fixed points is the perpendicular bisector of the straight line joining the points Gradients of PQ = (5-3 / 3-1) = 2/2 = 1
Gradient bisector = -1
Equation of perpendicular bisector
y - y1 = m(Ο - Ο1
y - 4 = -Ο + 2
y = -Ο + 6
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